Many large creatures reside in the oceans that are huge and have been around for millions of years. Learn about one such creature, the lion’s mane jellyfish, in this AnimalSake article.
Did You Know?
The largest recorded lion’s mane jellyfish was carried by the waves and found on the shores of Massachusetts Bay in 1870. Its body (bell) diameter was 7 feet 6 inches (about 2.3 meters), and its tentacles were a record 120 feet (about 37 meters) in length, which is longer than most blue whales.
The lion’s mane jellyfish (Cyanea capillata) is the largest known species of jellyfish that belongs to the phylum Cnidaria and class Scyphozoa. This jellyfish, also called hair jelly, gets its name after its color and appearance of the huge entangled mass of tentacles that resembles a lion’s mane.
It is a huge creature, and many oceanic creatures, like shrimp and small fish may live in the manes of this jellyfish, for safety and getting regular food supply.
Lion’s mane jellyfish are found in the North Atlantic as well as the Pacific waters near Australia. They also dwell in the coasts of Britain, Norway, and the United States. They are generally found in the cooler regions of the Pacific and Atlantic oceans, as they are unable to cope with the warmer waters.
➦ The tentacles of these jellyfish may differ in length. They have 8 bunches of tentacles, ranging between 70 to 150, in each bunch. These tentacles are extremely sticky and silvery white in color, which emanate from the bell’s subumbrella or the concave inner surface of the jellyfish.
➦ The bell of the jellyfish is divided into eight lobes, which possess flamboyant arms that erupt from the center of this bell. The color of the bell undergoes a change as the jellyfish ages and becomes more colorful. It ranges from crimson to purple in larger specimens, while the smaller ones display orange to tan color range.
➦ This jellyfish is often bioluminescent, which means it produces its own light. Thus, it glows in dark waters.
Habitat and Behavior
➦ The lion’s mane jellyfish reside in cold waters and are unable to cope with warm waters. They are ocean dwellers for majority of their lives; however, towards the end of their lifespan, they tend to reside in shallow waters.
➦ The lion’s mane jellyfish do not go down beyond 20 m and can move vertically. However, they depend on the ocean currents and wind to travel long distances. They are mostly spotted in large numbers during summer and autumn, when food is abundant.
➦ Like all other jellyfish, these jellyfish can reproduce sexually as well as asexually (in the polyp stage).
➦ They pass through four different stages in their lifespan that last through a year: (i) larval stage; (ii) polyp stage; (iii) ephyrae stage; and (iv) medusa stage.
➦ The female jellyfish carries the fertilized eggs in the tentacles where they grow into a larva. After the larvae are old enough, the female deposits them on a hard surface, where they advance to the next polyp stage. The polyps then asexually reproduce, which create small ephyraes. The ephyraes then break off and individually grow to the medusa stage, eventually evolving into a fully-grown jellyfish.
Its Sting and Contact with Humans
➦ The tentacles of the lion’s mane jellyfish bear stings that help it to catch its food which includes zoo plankton, sea birds, larger fish, sea turtles, and other jellyfish.
➦ The sting causes temporary pain and redness in humans; however, the stings are not known to be fatal. Symptoms include a rash, itching, blistering, or muscle cramps. Some people are said to develop an allergic reaction, while in worst cases, it alters the heart rate and leads to respiratory problems.
➦ An encounter with humans was recorded on July 21, 2010, when about 150 people were thought to have been stung by a twenty-two kilogram dead lion’s mane jellyfish, which had broken into many pieces in Wallis Sands State Park in New Hampshire (USA). Considering the size of this species, it is believed that the incident was possibly caused due to a single specimen.
➦ Another interesting reference is that the lion’s mane jellyfish appears in the Sherlock Holmes story, “The Adventure of the Lion’s Mane.” In this story, Holmes discovers at the end that the school professor who died after he went swimming was actually killed after being stung by the lion’s mane jellyfish. The initial suspect was the professor’s rival in love who was similarly attacked by the jellyfish and survived the attack. The professor had a weak heart, and hence, succumbed to the attack.
➦ The application of vinegar helps reduce the pain from this jellyfish sting.
➦ Some jellyfish in the larval stage pull through the harsh winter season, and then feed excessively in the summer months, as warm weather encourages plankton growth. They are known to reproduce during spring.
➦ They cleverly feed by beginning from close to the surface of water. They then sink slowly, spreading their tentacles in the form of a wide “net.” The net is hardly visible, so everything around gets trapped.
➦ The tentacles carry poisonous stingers, and the venom from them are enough to stun humans. With the help of these tentacles, the food makes its way into the mouth.
➦ The stingers remain venomous even several days after the jellyfish dies. The reason being the tentacles, that break away, could get stuck in the fishing nets, for example, and people handling these fishing nets may get stung.
Its status is yet to be assessed by the IUCN, while at present, there are no major threats reported against this jellyfish. There are no special conservation efforts in place for the lion’s mane jellyfish at this point.